The material is an answer, not a starting point

Enquiries often arrive with the material already decided. Sometimes that is right, but a grade chosen before the duty is described is a guess, and guesses get re-quoted. Describe what the part does, where it sits, and what it has to survive — the material follows from that, and it is often not the one that was assumed.

Four answers before anything can be quoted

  • What the part does — the function in the machine, not just the shape.
  • What it has to fit — the mating part, and which dimensions are functional.
  • The conditions it runs in — peak temperature, whether it cycles, the medium, the load, the electrical duty.
  • The quantity band and the lead time you are working to.

What to put on the drawing

  • Full geometry, with the datum stated — which face or diameter everything else is measured from.
  • Tolerances on the functional surfaces only. Tolerancing everything to the tightest number adds cost without adding fit.
  • Flatness, diameter or straightness with the area or length over which it applies. A plate flat over its whole face is a different part from one flat only where it seals.
  • Surface finish where the part seals, slides or is measured against — and explicitly where it does not matter.

The five things that stall an enquiry

  • A tolerance written as “as accurate as possible”.
  • No indication of which surfaces are functional.
  • No operating temperature, or only a peak figure with no cycle pattern.
  • No quantity, so the forming route cannot be chosen.
  • A physical sample with no dimensions and no photographs of it in place.

What comes back

Once the four answers are in place, the reply is a proposed grade, a forming route, the inspection points that will be checked, and a quotation with a lead time against the agreed specification — followed, where the part is new, by a sample stage before batch production.

Keep the drawing and the part together

If you are sending a sample, send photographs of it in place along with at least the critical dimensions. A worn sample tells us the failure mode; photographs tell us what it presses against. Both together usually shorten the loop by a round of samples.